I've set up XOOPS site and I've configured it to my liking, and I've deleted/make unavailable the main menu for the anonymous user by unchecking the main menu in the admin/blocks configuration. But after a while I found out that the main menu just disappears, even from the registered users menu, though it still appears to be available (ie the block is checked to be accessible)from admin/Groups/Registered user. Can anyone help me to bring back the main menu??

I think you have to make the menu available again and have to disable it for the unregistered users in the groups-menu...
There you have to select the anonymous users and disable the main menu...

Correct me if i was wrong...

That's just what confuse me. How to make the menu available??